14.6 Assumptions for Matching

Conditional Independence

The set of matching variables you’ve chosen is enough to close all back doors.

Common Support

• Matching assumes that there exist appropriate control observations to match.

Look at the distribution of a variable for the treated group against the distribution of that same variable for the untreated group

Balance

Balance Table

• Shows differences

  • between treated and control groups
  • for means, deviations, etc.
  • for several variables

• Create table columns

  • unmatched data
  • matched data